The cheapest place to buy them is on eBay. Just do a search for "softail lowering"

 

i protest the sloptail thing
I like my SOFTtail and will corner with best of the
dyna's plus it has the old school look
if I had wanted shocks sticking out I could have kept my kawa or bought any number of
rice burners ( actually still have the 1500 kawa son rides it )

 

i wont put the lowering kit on mine. my brother-in-law has it on his 96 fxsts and the hes going to put it back stock, says the ride sucks and he scrapes, looks cool but if you want to ride id leave it alone.

 

I have the Progressive lowering kit studs on my 04 FXST and love it. Half of my ridding is w/ wife with a combined waight of 300 lbs. It is a tad ruffer than stock but not much. Wife didn't complain when I but them on. I only lowered it about an inch and a half. We load it up with around 50 extra pounds of gear when we take trips and no problems. It will scrape the bottom of my V&H big shot staggard if I get on it to hard in a tight curb but you learn pretty quick. If I had wanted a 50 degree lean angle I wouldn't have got a Hog. I got 23000 miles on this set up so far. Unless you really like to lay down the curves it's fine.

 

I have a torsion bar suspension on my bike....it allows me to raise or lower my *** end two inches with a 5/8" box wrench. When I pull up to bike night, I whip out my trusty wrench, lower the bike till it's sitting on the bike and wait for the ooh's and ahh's! When it's time to go home or ride two up, I raise it back up to riding height.